Binary relay utilizing armature inertia for shifting binary positions



May 13, 1969 R. o. WHITAKER 3,444,491

BINARY RELAY UTILIZING ARMATURE INERTIA FOR SHIFTING BINARY ITIONS Filed Dec. 5.

20 f-az United States Patent 3,444,491 BINARY RELAY UTILIZING ARMATURE INERTIA FOR SHIFTING BINARY POSITIONS Ranald 0. Whitaker, 3145 N. Delaware, Indianapolis, Ind. 46205 Filed Dec. 5, 1966, Ser. No. 599,036 Int. Cl. H01h 67/02 US. Cl. 335-128 8 Claims ABSTRACT OF THE DISCLOSURE An electromagnet fixed to a base is positioned between the arms of a U-shaped armature. The armature is pivotally mounted to the base so that as one arm is drawn to the magnet, the other moves away. For the oflf condition of the electromagnet, the armature has two stable positions. The first is with the first arm nearer the magnet. The second is with the second nearer the magnet. Consider the armature to be in the first stable position. When the magnet is activated, the first arm is drawn to the magnet, operating electrical contacts associated with the armature, and distorting a spring. When the magnet is deactivated, energy stored in the return spring throws the armature to the second stable positions. Upon a second activation of the electromagnet, the second arm is drawn to the electromagnet, operating associated electrical contacts if any, and distorting a return spring. Upon a second reactivation, the spring returns the armature to the first stable position.

This invention relates to relays of the flip-flop variety. Such relays operate an output circuit on every other input signal. More particularly this invention relates to the mechanical arrangement of the relay for effecting this binary action.

In accordance with the invention, a V-shaped soft iron armature is pivoted to a frame. An electromagnet fixed to the frame is positioned between the open ends of the armature. In general, one of the arms of the armature will be nearer the magnet than the other. This arm shall be designated the first arm. Activation of the magnet causes this first arm to close to the magnet. Simultaneously the second arm is moved further away. This closing of the first arm distorts a Spring. When the magnet is deactivated, the spring throws the armature to a position in which the second arm is nearer the magnet. A second activation of the magnet causes the second arm to close to the magnet, again distorting a spring while closing. The second deactivation of the magnet permits the spring to throw the armature assembly to its original position. Contacts are placed on the armature assembly and supporting base structure to effect desired switching actions.

Binary relays presently in use generally cause the magnet to simultaneously distort a return spring and drive a mechanism which swings a contact making device from one output circuit to the other. Causing the magnet to simultaneously perform two functions necessitates a larger magnet and more magnet power. The present invention requires the magnet to distort the return spring only. Energy stored in the return spring is used later to swing the contact making device. Consequently a binary relay constructed according to the present invention may use a smaller magnet and will not require as much power.

Accordingly it is the object of the present invention to provide a binary relay which requires the magnet to distort the return spring only. Energy stored in the spring is later utilized to effect the output swinging function. The

attainment of this object permits cost of magnet to be reduced. It permits magnet power to be reduced.

Referring to the drawings:

FIG. 1 is a perspective view of a basic relay built in accordance with the present invention.

FIG. 2 is a sectional view of a preferred magnet configuration.

FIG. 3 is a perspective partial view of a relay incorporting a variation in electrical contacts.

FIG. 4 is perspective partial view of a relay incorporating multiple contacts.

FIG. 5 is a perspective partial view of a relay incorporating a modified spring structure.

FIG. 6 is a perspective partial view of a relay having multiple contacts and incorporating the modified spring structure.

FIG. 7 is a frontal partial view of a relay incorporating a biasing spring.

FIG. 8 is a frontal partial view of a relay in which the springs are attached to the frame.

Referring to FIG. 1, a frame consisting of base 2, upright 4 of electrically insulating material, and post 6 is provided. An armature consisting of pivot 8, arm 12, and arm 14 is rotatably mounted to the frame assembly by pin 10 fixed to pivot 8 and passing through clearance holes in upright 4 and post 6. A spring washer 16 between post 6 and pivot 8 provides a consistent resisting torque to rotation of the armature relative to the frame. Fixed to upright 4 is magnet 18.

Magnet 18 is shown in detail in FIG. 2 and consists of a soft iron core 182, two washer type polepieces of soft iron 183 and 184 pressed to core v182, and a coil 186. The structure is such that a soft iron plate 188 is strongly attracted toward the magnet whenever the magnet is activated 'by passing a current through coil 186.

Referring again to FIG. 1, also fixed to upright 4 are stops 20 and 22. Fixed to pivot 8 is cylindrical wire spring 24. The placement of stop 20 is such that spring 24 touches stop 20 at a time when arm 12 is still from 1 to 2 millimeters away from the polepieces of magnet 18. Activation of magnet 18 causes arm 12 to close, moving over this short distance and distorting spring 24. By proper choice of stiffness of spring 24 the major portion of the mechanical energy produced during the closing action may be converted to distortion energy within spring 24. When magnet 18 is deactivated, spring 24 throws the armature to the right. The kinetic energy of the moving armature is dissipated by spring 16. The armature is brought to rest with arm 14 nearer than arm 12 to magnet 18. In the ideal case, motion would cease with spring 24 resting against stop 22.

The next activation of magnet 18 causes a similar action involving stop 22.

Fixed to arm 12 is electrical contact 26. Fixed to upright 4 is contact 28. When arm 12 closes to magnet '18, contact 26 is brought to bear against contact 28. Electrical connections from an external circuit may be made to arm 12 and contact 28.

FIG. 1 depicts the simplest embodiment of the present invention. It depicts a single contact pair which is closed on each second activation of the coil. It is essentially a single-pole single-throw switch.

As indicated in FIG. 3, addition of a contact 30 to arm .14 and a contact 32 to upright 4 converts the unit into a single-pole double-throw switch. This may be converted into a double-pole single-throw alternate-binary switch by making pivot 8 of nonconducting material.

A multipole arrangement is illustrated in FIG. 4. A header 34 of insulating material is fixed to upright 4. It carries contacts 36, 38, and 40. Insulator 42 is fixed to arm 12. Fixed to insulator 42 are spring contacts 44, 46, and 48. A similar arrangement is provided on the left side of header 34. The result is a two triple-pole single-throw alternate-binary switch. The first switch is closed on one activation of magnet 18; the second on the next. Any number of such contacts may be provided.

All contacts fixed to arm 12 which have been shown thus far have been of the leaf spring variety. Spring are preferred to solid contacts because they eliminate contact bounce. In the structure of FIG. 4, spring contacts are practically mandatory to assure that all contacts are made.

It is apparent that the springs may be fixed to the frame rather than the armature. Such structure is shown in FIG. 8. Fixed to header 34 are Springs 80 and 82. Fixed to spring 80 is stop 84 of insulating material. Also fixed to spring 80 is contact 86. Fixed to arm 12 and directly opposed to contact 86 is contact 88. As shown in FIG. 8, when magnet 18 is quiescent, stop 84 prevents contact 88 from touching contact 86. When magnet 18 is activated, arm 12 moves to the left Spring 80 flexes and contact 88 makes with contact 86. A similar action involving arm 14 and spring 82 takes place.

The pull of the magnets thus far discussed is divided between countering the force developed by spring 24, developing a force on the electrical contacts brought together, and developing a force clamping the arm involved to the magnet polepiece, It is desirable that all the pull of the magnet be used to develop force on the contacts. It is desirable to eliminate spring 24. This may be accomplished through utilization of the structure of FIG. 5. Spring 26 has bar 50 fixed to its end. Stop 52 is fixed to upright 4 in such position that bar 50 rests against it while arm 12 is still between 1 and 2 millimeters from contact with magnet 18. Contact 28 is fixed to upright 4 in such position that it will intercept bar 50 when arm 12 is about a half millimeter from contact with magnet 18. Activation of magnet 18 causes bar 50 to first make electrical contact with contact 28. Further movement of arm 12 toward closure with magnet 18 causes flexure of spring 26 which in turn lifts bar 50 from stop 52. When arm 12 is in closed position the force of magnet 18 is divided between contact force and force clamping arm 12 to magnet 18, No force is required to overcome a separate return spring. The structure of FIG. 5 combines in spring 26 the functions of contact spring and return spring. This principle is discussed further in concomitant patent application Ser. No. 599,037, filed Dec. 5, 1966, entitled High Contact Force Relay.

The principle of FIG. 5 may be extended to a multipole relay as indicated in FIG. 6, A header 34 of insulating material supports contacts 36, 38, and 40. Header 34 carries lip 342 extending so that it intercepts bar 50 before bar 50 touches contact 40. FIG. 6 shows the position of parts before magnet 18 is activated. When magnet 18 is activated, arm 12 moves to closed position. Bar 50 makes contact with contact 40 and lifts from lip 342. Similar action involving contacts 36 and 38 takes place. The contact structure of FIG. 6 constitutes a triple-pole single-throw switch. A similar switch may be provided on the opposed face of header 34. The structure of FIG. 6 may be extended to provide a number of additional contacts.

Referring again to FIG. 1, the next activation of magnet 18 will cause closure of arm 12 to magnet 18. Upon deactivation of magnet 18, spring 24 will throw the armature clockwise. If the damping torque produced by spring 16 is optimum, the armature motion will be arrested with spring 24 just touching stop 22. This minimizes the distance between arm 14 and magnet 18. Consequently the electrical power required for pulling arm 14 at the next activation of magnet 18 is minimized, It follows that the adjustment of the damping torque of spring 16 is critical. Also, the damping torque Optimum for clockwise swings will generally not be optimum for counterclockwise swings. Stops 20' and 22 may not be symmetrically placed with respect to spring 24. Consequently closure in one direction results in more energy being stored in spring 24 than closure in the opposite direction.

4 It is apparent that the armature will because of gravity assume prior to magnet activation one or the other of the two binary open positions. Refer to this first position which it assumes as the first binary open position.

Theoretically the armature can assume a position exactly midway between the two binary open positions. However, this is a position of unstable equilbrium. A jar or a vibration will cause the armature to upset and fall to one of the two open positions,

It is apparent that spring or magnetic means may be provided to effect the over-center action and to cause the armature to assume a binary open position prior to magnet activation.

FIG. 7 presents a modification which will insure that armature swing is always arrested with spring 24 resting against one of the stops. A leaf spring 52 is fixed to the arms of the arms of the armature. A tie 54 is passed from the midpoint of spring 52 to a pin 56 positioned directly below pin 10. The arrangement is such that an upsetting action ensues which will insure that the armature will always stop with spring 24 against one of the stops. Several other spring configurations are possible. The configuration of FIG. 7 is illustrative only. In particular, an over-center spring may be employed such as is used in microswitches, Such a spring would render impossible any stoppage of the armature at exactly midpositionwhich is noted to be a position of unstable equilibrium.

Many variations from the preferred structure shown in the figures are possible. The magnet may assume different forms. Bearing friction associated with an oversized pin 10 may be employed to eliminate the need for damping spring 16. Arrangements may be devised in which gravitational forces eliminate the need for the springs which bias the armature toward midposition. In all embodiments shown, electrical contacts have been made upon closure of the relays. The relays have been nor mally open. By placing contacts on the stops of FIG. 5 and incorporating the spring system of FIG. 7, a normally closed relay results. Many such variations are possible without departing from the basic principle of the present inventionwhich is the storage during relay closure of energy in a spring and the use of this stored energy upon relay release to throw an armature across a dead zone and into the companion binary position.

The following is claimed:

1. A binary relay comprising:

a frame;

an electromagnet mounted to said frame;

an armature pivotally mounted to said frame;

said armature having first and second arms of magnetic material arranged on opposite sides of said electromagnet;

said arms arranged in cooperative relationship with said electromagnet;

said armature having a first binary open position in which said first arm is near said electromagnet, a second binary open position in which said second arm is near said electromagnet, a first binary closed position in which said first arm closes with said electromagnet, and a second binary closed position in which said second arm closes with said electromagnet;

said armature being mounted in an over-center manner thereby assuring that said armature assumes a binary open position prior to activation of said electromagnet;

elastic means coupled between said frame and said armature for biasing said armature toward midposition when said armature is outside the range between said first binary open position and said second binary open position; and

electric switch means having first contacts associated with said armature and second contacts associated with said frame, said switch means being operated only while said armature is in said first binary closed position;

said armature, when in said first binary open position, moving upon activation of said electromagnet to said first binary closed position, said movement causing said elastic means to distort;

said elastic means, when said armature is in said first binary closed position, because said armature to be thrown to said second binary open position upon deactivation of said electromagnet;

said ar -mature, when in said second binary open position, moving upon activation of said electromagnet to said second binary closed position, said movement causing said elastic means to distort;

said elastic means, when said armature is in said second binary closed position, causing said armature to be thrown to said first binary open position upon deactivation of said electromagnet.

2. A binary relay as in claim 1, and having an overcenter spring means coupled between said armature and said frame for biasing said armature awa from midposition, said spring means being dominant over said elastic means only while said armature is between sid first binary open position and said second binary open position.

3. A binary relay as in claim 1, said elastic means comprising one or more leaf springs fixed at one end to the free end of said first arm and one or more leaf springs fixed at one end to the free end of said second arm, said elastic means being adapted to be intercepted by and distorted by said frame on closure of said armature.

4. A binary relay as in claim 1, said elastic means being one or more leaf springs fixed at one end to said frame and adapted to be intercepted by and distorted by said armature upon closure of said armature to said electromagnet. I

5. A binary relay as in claim 1, said elastic means being one or more leaf springs fixed at one end to the free end of said first arm and one or more leaf springs fixed at one end to the free end of said second arm, said springs being adapted to be intercepted by and distorted by said frame on closure of said armature, and having stops fixed to said frame and adapted to intercept said leaf springs prior to operation of said electric switch, flexure of said leaf springs attending operation of said electric switch adapted to cause said leaf springs to lift from said stops.

6. A binary rela as in claim 1, said elastic means being one or more leaf springs fixed at one end to said frame and adapted to be intercepted by and distorted by said armature upon closure of said armature to said electromagnet, and having stops fixed to said armature and adapted to intercept said leaf springs prior to operation of said electric switch, fiexure of said leaf springs upon operation of said electric switch causing said leaf springs to disengage from said stops.

7. A binary relay as in claim 1, and having a second electric switch means with first contacts on said armature and second electric contacts on said frame and adapted to be operated when said armature moves from said second binary open position to said second binary closed position.

8. A binary relay as in claim 1, and having frictional means between said armature and said frame, having sufficient magnitude to stop said armature in said second binary open position when said armature is released from said first binary closed position and to stop said armature in said first binary open position when said armature is released from said second binary closed position.

References Cited UNITED STATES PATENTS 2,891,199 6/1959 Ugon 335-279 2,997,560 8/ 1961 Callaway 335-128 3,319,197 5/ 1967 Yakuwa 335-95 BERNARD A. GILHEANY, Primary Examiner.

D. M. MORGAN, Assistant Examiner.

US. Cl. X.R. 3 -203 

